Three 345-kV lines connecting South Fond du Lac Substation to the Columbia, Edgewater and Fitzgerald Substations, and

A 138-kV network in the Fox River Valley/Green Bay area.

Transmission system limitations in Zone 4

In our analysis of Zone 4 we identified potential high voltages in the Outagamie and Calumet County areas and low voltages in the Brown County area. In addition, other studies occurring in parallel with this Assessment, including Northern Area Reliability Assessment, have identified several voltage and thermal limitations. The most severe limitations occur during the off-peak periods. See the Zone 2 section for a summary of a preliminary preferred alternative.

Electric system overview

Increases expected in population, employment – Population in Zone 4 is projected to grow 0.8 percent annually between now and 2023. Brown County is expected to realize the largest increase in population. Employment is projected to grow 1.0 percent annually in the same time period, with the largest increase projected in Brown County.

Electricity usage growing

Peak electric demand typically occurs during the summer months, although the northern portion of Zone 4 typically experiences nearly equal summer and winter peaks. Paper mills and foundries in the Green Bay and Appleton metropolitan areas are some of the largest electricity users in the zone.

Electric load is forecasted to grow at approximately 0.4 percent annually through 2024. Also, locally generated electricity is declining in the area with smaller, coal-fired generators most at risk. This includes generation owned by industries, municipalities and utilities.

Transmission projects in Zone 4

The most notable planned, proposed and provisional network projects and asset renewal projects in Zone 4, along with their projected year of completion and the factors driving the need for the projects, are listed below.